This is the default mode for the media just delete the directory to customized the upload settings.
Go to configuration and click media.
File extensions which are accepted in the media browser. Use spaces to separate (e.g. “jpg gif pdf doc”).
Note that this can be overriden on a per-field basis when creating multimedia asset fields and files of certain extensions cannot be embedded at this time.
Directory mode: jpg jpeg gif png txt doc xls pdf ppt pps odt ods odp mp3 mov m4v mp4 mpeg avi ogg wmv ico